It is known to provide an apparatus for cutting, printing or embossing consecutive parts of a continuous sheet of material. Such an apparatus has a rotatable tool cylinder with a tool plate mounted thereon for cutting, printing or embossing the consecutive parts of the continuous sheet. The apparatus has an anvil cylinder adjacent to the tool cylinder, the continuous sheet passing between the anvil cylinder and the tool cylinder. During operation of the apparatus the continuous sheet has a constant speed through the apparatus, and the tool cylinder has a fixed speed of rotation. Tool cylinders having different diameters may be used with the apparatus. Such an apparatus may be termed a “full-rotary” apparatus.
It is also known to provide a “semi-rotary” apparatus for cutting, printing or embossing consecutive parts of a continuous sheet of material. Such an apparatus has a support which has rollers over which the continuous sheet runs, and the support is movable during operation of the apparatus to set the correct position for the consecutive parts of the continuous sheet. During operation of the apparatus the continuous sheet is required to have a variable speed through the apparatus. Furthermore the tool cylinder is required to have a constant speed of rotation during operation of the apparatus. Such an apparatus is typically used with a tool cylinder having a fixed diameter.
It is further known to provide an apparatus for cutting, printing or embossing alternate parts of a continuous sheet of material. Such an apparatus has a rotatable tool cylinder with one or two tool plates mounted thereon for cutting, printing or embossing the alternate parts of the continuous sheet. The apparatus has two anvil cylinders adjacent to the tool cylinder, the continuous sheet passing between the anvil cylinders and the tool cylinder. A support of the apparatus has two rollers over which the continuous sheet runs, and is mounted between the two anvil cylinders. The support is movable to set a phase position of the anvil cylinders and the tool cylinder so that cutting, printing or embossing occurs at the correct position of the alternate parts of the continuous sheet. The position of the support is set prior to operation of the apparatus and is in a fixed position during operation thereof. During operation of the apparatus the continuous sheet has a constant speed through the apparatus, and the tool cylinder is required to have a variable speed of rotation when not cutting, printing or embossing depending on an angle of the one or two plates mounted on the tool cylinder.
A problem associated with the known apparatus is when the tool cylinder has a variable speed of rotation. Typically the tool cylinder has a relatively large mass which means that changes in rotational speed thereof may be problematic particularly when the apparatus is operating at high production rates. In effect the requirement for a variable speed of rotation of the tool cylinder limits the speed of operation of the apparatus to cut, print or emboss the continuous sheet of material.
A problem associated with the known “full-rotary” apparatus is that it may require tool cylinders of different diameter to mount different tool plates thereon for cutting, printing or embossing. The tool cylinders of different diameter may be required when performing different tasks. The tool cylinders are expensive, and the requirement for different tool cylinders depending on the tool plate for cutting, printing or embossing increases the operational and capital cost of the apparatus. Furthermore, the requirement for multiple tool cylinders reduces the operational flexibility of the apparatus to change between different tasks because the tool cylinder must be selected and fitted prior to operation of the apparatus.
A problem with the “semi-rotary” apparatus is that the continuous sheet may be required to be stopped and reversed using the movable support to ensure that the consecutive parts are in the required position on the continuous sheet. Such stopping or reversing may be problematic particularly when the apparatus is operating at high production rates. In effect the requirement to stop or reverse the continuous sheet limits the speed of operation of the apparatus to cut, print or emboss the continuous sheet of material.
It is broadly an object of the present invention to address one or more of the above mentioned disadvantages of the previously known ways of cutting, printing or embossing.